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HIRESFI AMPER502 Full Digital Amplifier Test

Ouch, "don't be too proud of this technological terror you've constructed"
 
I recall Wadia made a 'power dac' type device, or was that just marketing rather than true circuit implementation? At any rate, I'd hope that performed well given their price and pretty enclosure!
 
Must have been Bruno Putzeys, who, in this very interesting lecture, concluded "Keep in mind that no converter designer in their right mind would ever consider building a DAC using power FETs" (from 35'54''):

32.09 into the video Bruno talks about a lousy class D amp that gave class D a bad name but still sells. Anyone know what amp he's talking about?
 
THANK YOU AMIRM!
Interesting even if broken.
You've been working overtime lately!

Pic not related
 

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But it doesn't properly solve the speaker impedance dependency, among other things. Relative to using an ADC, this is actually an elegantly simple, but ultimately incomplete, solution ;)
Bingo, and this is why feedback really has to be taken as close to the load as possible. You can't cheat physics; the load is the most unpredictable part of the system.

That said, I can't help being curious about the NFB implementation @IVX has in the PowerDAC v2.1... =)
 
The STA350BW contains DSP so I assume they're using that rather than use a higher spec ARM processor to do it in software.
This is most probably the case. All DSP functions shown in promotional video are prsesent in STA350BW-s DSP and on developers site is Information "With a team of latest technology 32bit ARM micro-controller and coloured OLED display" and image what confirms that ARM is only for controlling STA and display.
I have made SPDIF input 2-way active speakers with STA350. Relatively OK, only STA350 distortion and noise are little high.
Old versions of JBL LSR305, JBL306 and some others have same STA350 inside: https://www.audiosciencereview.com/forum/index.php?threads/inside-the-jbl305p-mkii.17346/
 
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32.09 into the video Bruno talks about a lousy class D amp that gave class D a bad name but still sells. Anyone know what amp he's talking about?
It was sympathetic of Bruno to omit the name of the offending amp, but it wasn't very difficult to find.

That particular Stereophile test was of the Pass Labs X1000 monoblock power amplifier, which isn't too surprising.


1726908785059.png
 
No, it was not this amp Mr Putzeys referred to, because the Pass Labs is not a class D amp.
 
No, it was not this amp Mr Putzeys referred to, because the Pass Labs is not a class D amp.
I was responding to the Stereophile IMD test of the anonymous 455W amp because that was the snapshot in your post #39.

Sorry, I've no idea what the noisy class D amp is.
 
This is most probably the case. All DSP functions shown in promotional video are prsesent in STA350BW-s DSP and on developers site is Information "With a team of latest technology 32bit ARM micro-controller and coloured OLED display" and image what confirms that ARM is only for controlling STA and display.
I have made SPDIF input 2-way active speakers with STA350. Relatively OK, only STA350 distortion and noise are little high.
Old versions of JBL LSR305, JBL306 and some others have same STA350 inside: https://www.audiosciencereview.com/forum/index.php?threads/inside-the-jbl305p-mkii.17346/

I came here to note the same thing, that its used in the LSR305 MK2, because I was considering making a mod to override the settings sent by its own microcontroller to expose more functionality of the STA350. It's a very capable little chip.
 
I came here to note the same thing, that its used in the LSR305 MK2, because I was considering making a mod to override the settings sent by its own microcontroller to expose more functionality of the STA350. It's a very capable little chip.
I use Arduino UNO to write setting to STA350, also volume control is made with Arduino.
 
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